Method of reducing metals.



R. J. McNlTT.

METHOD 0F REDUCING METALS.

APPLICATION FILED MAY l2. l9l5.

Patented Feb. 6, 1917.

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ROBERT J. MCNITT, OF NIAGARA FALLS, NEW YORK, ASSIGNOR TO THE ROESSLER &

` HASSLACHER CHEMICAL CO., 0F NEW YORK, N. Y., A CORPORATION OF NEW YORK.

METHOD 0F REDUCING METALS.

Specification of Letters Patent.

Patented Feb. 6, 1917.

Griginal application filed January 2, 1913, Serial No. 739,710. Divided and this application filed May 12,

\ 1915. Serial No. 27,474.

- To all whom t may concern.'

Be it known that I, ROBERT J. MGNITT,

residing at Niagara' Falls, county ofNiagara, and State of New York, have invented a certain new and useful Method of Reducing Metals, of which the following is a specification.'

My invention relates to a new and useful method of reducing metals from compounds containing the same and it refers particularly to the reduction of metals from their compounds by electrolyzing the same under pressure.

In my copending patent application Serial No. 739,710, filed January 2, 1913, of which this is a division, I broadly disclosed my invention of an improved method for the electrolytic reduction of metals consisting in carrying on the electrolysis under pressure, the pressure specifically described and claimed in the original application be- -ing that due to a gas compressed against y the upper surface of the electrolyte. In my said original application I stated that the same improvement in the electrolysis of metals could be secured by carrying on the electrolysis under the pressure due to a superimposed column of electrolyte which method I shall now more fully explain by describing, as an example, the electrolysis of metallic sodium from molten sodium chlorid. I shall explain this form of my invention by reference to the accompanying drawing, which is a vertical longitudinal section showing in rather a diagrammatic way one form of apparatus suitable for the purpose.

A indicates the anode which may be of graphite or other suitable material. It is electrically connected with conductors B extending through the walls of the vessel. The cathode C, of any suitable material is shown as connected on its lower side with a conductor Dvextending through the bottom of the vessel. The walls of the vessel may be formed of steel plates E lined on the inside with a layer of asbestos F, the space between said walls and the rear sides ofthe anodes and above the said anodes being -filled in with a suitable material such as brick work Gr, preferably lire-clay brick. The working chamber of the vessel extends from vthe bottom X up to the cover H.

Z `indicates a bell of any suitable material, shown as somewhat larger in its lateral extension than the cathode C.

K represents a diaphragm of perforated metal extending from the lower rim on the bell Z downward between the anode and cathode, the lower rim being shown as terminating a short distance from the upper edge of the cathode C.

Z indicates a tube connected to the upper part of the bell Z and passing through the cover H. A pipe N branches from the tube Z and connects it to a receiver which is provided with a valve O. The pipe I serves to'conduct away the gases generated during the process and another pipe Q pro* vided with a cover serves for charging the lmetallic compound (in the presumed inand degree of purity of the electrolyte, the

proximity of the fusing point of the electrolyte to the boiling point of the metal separated, the current density employed, and the shape and surface conditions of the electrodes. In the example cited the column of molten sodium chlorid should? be carried tosuch a heightabove the zone -of electrolysis that it shall exert a pressure of at least one pound per square inch in said zone of electrolysis. Electric current is then passed through the electrolyte, decomposing the same with liberation of chlorin gas at the anode, and metallic sodium at the cathode. The chlorin passes up through the electrolyte, and escapes by way of the pipe P. The metallic sodium liberated at the cathode, rises into and is collected under the bell Z. f

As the continuous electrolysis constantly increases the volume of metallic sodium within the bell, owing to the difference in the specific gravity of the respective liquids the sodium rises in the bell g and finally overflows through the pipe N into the receiver O.

Many modications in the way of conducting the process described may be made, without departing from the nature of my invention.V For instance the form and construction of the bell Z may be modified so as to allow the introduction of the cathode C and its conductor I) from the top instead state; the high column of fluid exerting the pressureon the Zone of electrolysis consists preferably of the molten electrolyte, but it may partly or even entirely'be substituted by other suitable liquid substances'. The vessel 'may be square or round or of anyy other suitable shape.

The apparatus hereinbefore described is well suited for the purposes of my invention for the production, for instance of metallic sodium from its compounds,.preferably sodium chlorid, but other metals may be similarly obtained from their compounds and my invention is not limited to the use of the particular apparatus which I have described and illustrated.

I claim: y V

l. A method of reducing metallic compounds to their metals, consisting in subjecting the molten metallic compounds in the zone of electrolysis to comparatively great hydrostatic pressure during the electrolytic process.

2. A method of reducing metallic compounds to their metals by electrolysis, consisting in subjecting the molten metallic compounds in the zone of electrolysis to the pressure of a column of fluid high relative to the cross section of the electrolytic chamber and electrolyzing the metallic compounds l under the pressure thus exerted.

3. A method of reducing metallic compounds to their metals by electrolysis, consisting in subjecting the molten metallic compounds in the zone of electrolysis to the pressure of a column of the molten Ametallic compound high relative to the cross section of the electrolytic chamber and then electrolyzing the same under the pressure thusv eX- erted. p

4. A method of reducing metallic compounds to their metals by electrolysis, consisting in introducing said metallic compounds forming the electrolyte, in a molten state, into the electrolytic zone, superimposing a high column of said molten metallic compounds on the Zone of electrolysis, passing the electric current through the bath of metallicv compounds, separating the products lgenerated at the electrodes as desired and controlling the applied pressure by the height of the column of the molten metallic compounds.

5. A method of reducing metallic sodium from its compounds, consisting in subjecting the molten sodium compound in the Zone of electrolysis to the pressure of a column of fluid high relative to the'cross section of the electrolytic chamber and then electrolyzing the sodium compounds under the pressure thus exerted. 4

6. A method of reducing metallic sodium from its compounds, consisting in subject# ing the molten sodium compound, forming the electrolyte, in the zone of electrolysis to the pressure of a column of said molten sodium compound high relative to the cross section of the electrolytic chamber and electrolyzing the same under the pressure thus exerted.

7 A method of reducing metallic sodium from its compounds by electrolysis, consisting in introducing said sodium compound forming the electrolyte, in a molten state, into the electrolytic Zone, superimposing a high column of the molten sodium compound on the zone of electrolysis, passing the electric current through the bath of said sodium compound, separating the products generated at the electrodes as desired and controlling the applied pressure by the height of the column of the molten sodium compound.

In testimony whereof I have signed this specification in the presence of two subscribing witnesses.

ROBERT J. MCNITT. Witnesses:

FRANK A. DUDLEY, H. W. CLARK. 

